Lubricant composition with improved varnish deposit resistance

ABSTRACT

In one embodiment, a lubricating oil with favorable deposit control is disclosed. The lubricating oil comprises, a major amount of base stock selected from the group consisting of Group II, Group III, GTL and any combination thereof, a mannich based dispersant comprising at least 0.1 and less than 2.0 weight percent of the lubricating oil, a demulsifier comprising a polyol ester and a poly oxyakylene, the demulsifiers comprising at least 0.002 to less than 2.0 weight percent of the lubricating oil, wherein the lubricating oil has a deposit control value less than 60 using 504 hour 120° C. Dry TOST sludge test. 
     In a second embodiment a method of deposit control is disclosed. In a third embodiment a method of formulating an oil to improve deposit control and emulsion properties is disclosed.

Non Provisional Application based on U.S. Ser. No. 61/072,432 filed Mar.31, 2008 which is based on Patent Memorandum 2006-PL-034.

BACKGROUND

The art or formulating lubricating oil compositions has become morecomplex as a result of increased government and user environmentalstandards and increased user performance requirements. Lubricants aretypically marketed based upon features such as fluid durability, depositcontrol, antiwear protection, filterability, water tolerance,rust/corrosion protection, and viscosity.

Deposit or varnish is a growing problem in many hydraulic and sensitivelubrication applications, such as gas turbine lubrication. Varnishformation is usually the result of a complex series of events which leadto lubricant degradation. There are two common causes of oildegradation. One cause is oxidation at elevated temperatures leading tothe formation of decomposition products, including acids and insolubleparticulate, referred to as deposits, varnish, sludge. The second causeis thermal degradation, such as, pressure induced dieseling ormicro-dieseling which occurs when entrained air bubbles are collapsedunder high pressure.

Deposit varnish is measured using a 504 hour 120° C. DRY-TOST sludgetest, which is a modified waterless ASTM D943 TOST test. This DRY-TOSTtest method was developed by Mitsubishi Heavy Industries in order toevaluate in short time the sludge or varnish formation tendency ofturbine oils. The Dry-TOST conforms to the ASTM D943 test with themodified conditions shown in the table below. After the 504-hr testperiod, leave the test tube to stand overnight at room temperature andthen measure the deposit amount. The sludge or varnish amount equals tothe amount of filter residues that 100 g of oil is filtered through a 1μm Millipore filter. A sludge amount of less than 100 mg/kg (ppm) is anacceptable result. The table below lists the items and test conditionsfor this test.

Items Test Condition Test Oil Quantity 360 ml Test Temperature 120° C.0.2° C. Oxygen Gas Flow Rate 3.0 0.1 L/h Water Not Added Catalyst Fe andCopper Wire

It is well known that API Group II and III base stock oils and GTL aretypically better than API Group I base oils. Group II and II base stocksare better because of the oxidation stability of hydroprocessed orhydrocracked base stocks as well as enhanced viscosity and temperatureproperties compared to conventional solvent refined base stocks.Consequently, many lubricants are being formulated with API Group II andIII base stock. A known deficiency of these non-polar, high saturatedAPI Group II and III base stocks are their lower ability to solubilizeor suspend lubricant degradation by-products in solution once formed.For this reason, API Group II/III based lubricants are more susceptibleto deposit formation once oil degradation has began.

A large number of failures in turbine-generator applications have beenassociated with varnish and sludge formation. Sludge and varnish areinsoluble materials formed as a result of either degradation reactionsin the oil, contamination of oil or both. Explanations typically includethe nature of the base oil, additive instability or degradation, bulkoil oxidation, electrostatic discharge, and low electrical conductivity,among others.

Recently, much attention has been directed to the potential role offluid electrification and electrostatic discharge as a prominentcontributor to sludge and varnish formation in turbine systems. Staticdischarge is a form of localized thermal degradation. Electrostaticcharge generation occurs in fluids systems as a result of internalmolecular friction and electrical potential between the fluid andmachine surfaces.

The magnitude of the static charge within the oil depends on manyfactors and grounding of the machine itself has little impact towardmitigating charge propagation. This is because the oil is nonconductiveand effectively self-insulates the charged fluid zones from groundedsurfaces. Once the charges build up in the working fluid zones,including reservoirs and filter housings, the subsequent staticdischarging may cause localized thermal-oxidative oil degradation.

There is a need to find a formulation that uses API Group II, Group III,and GTL base stocks in a formulation that provides favorable depositformulation properties. Accordingly, this invention satisfies that need.

SUMMARY

In one embodiment, a lubricating oil with favorable deposit control isdisclosed. The lubricating oil comprises, a major amount of base stockselected from the group consisting of Group II, Group III, GTL and anycombination thereof, a mannich based dispersant comprising at least 0.1and less than 2.0 weight percent of the lubricating oil, a demulsifiercomprising a polyol ester and a poly oxyakylene, the demulsifierscomprising at least 0.002 to less than 2.0 weight percent of thelubricating oil, the lubricating oil has a deposit control value lessthan 60 using 504 hour 120° C. DRY TOST sludge test.

In a second embodiment, a method to improve deposit control isdisclosed. This method comprises, obtaining a lubricating oil comprisinga major amount of base stock selected from the group consisting of GroupII, Group III, GTL and any combination thereof, a mannich baseddispersant comprising at least 0.1 and less than 2.0 weight percent ofthe lubricating oil, a demulsifier comprising a polyol ester and a polyoxyakylene, the demulsifiers comprising at least 0.002 to less than 2.0weight percent of the lubricating oil, wherein the lubricating oil has adeposit control value less than 60 using 504 hour 120° C. DRY TOSTsludge test and lubricating with the lubricating oil.

In a third embodiment, a method of formulating a lubricating oil toimprove deposit control and emulsion properties is disclosed. Thismethod comprises obtaining a major amount of base stock selected fromthe group consisting of Group II, Group III, GTL and any combinationthereof, a mannich based dispersant comprising at least 0.1 and lessthan 2.0 weight percent of the lubricating oil, a demulsifier comprisinga polyol ester and a poly oxyakylene, the demulsifiers comprising atleast 0.002 to less than 2.0 weight percent of the lubricating oil, andblending the base stocks, demulsifiers and dispersants to have a depositcontrol value less than 60 using 504 hour 120° C. DRY TOST sludge test.

DETAILED DESCRIPTION

The present invention will be described in connection with its preferredembodiments. However, to the extent that the following description isspecific to a particular embodiment or a particular use of theinvention, this is intended to be illustrative only, and is not to beconstrued as limiting the scope of the invention. On the contrary, it isintended to cover all alternatives, modifications, and equivalents thatare included within the spirit and scope of the invention, as defined bythe appended claims.

In one embodiment we have discovered a lubricant composition thatcomprises either a API Group II or III or GTL base stocks orcombinations thereof with antioxidants and other additive whenformulated with a specific mannich-based dispersant/demulsifiercombination yields an unexpected improvement in deposit control whilemaintaining good demulsability. Unexpectantly, not all dispersantsprovided this cleanliness benefit in this application.

While dispersants are known to improve deposit control, they are polarin nature and tend to be emulsive and provide poor water separation. Anadditional benefit in one embodiment of this lubricant composition isthat the final product also exhibit good demulsification by ASTM D-1401.This method is a rapid test that involves mixing together 40 ml of oiland 40 ml of water for 5 minutes at 1500 rpm with an impeller. Themixture is allowed to stand and the time for the water, oil and anyemulsion phase to separate is recorded. This test is conducted at 54° C.(130° F.) for viscosity below 90 cSt at 40° C. a generally acceptableresult is 30 minutes maximum time to 3 mls of emulsion remaining.

The acceptable treat ranges for the mannich based dispersants is atleast 0.1 to less than 2.0 weight percent. A preferred treat range is atleast 0.2 to less than 0.5 weight percent and a most preferred treatrange is 0.2 and less than 0.4 weight percent.

In a preferred embodiment, we have discovered that a Pluronic L 121Surfactant from BASF is effective at the same concentration as thepolyol ester. In a most preferred embodiment, the demulsifier alsoincludes a propylene oxide block copolymer. The preferred concentrationof the polyol ester and ethylene oxide in the demulsifier is at least0.001 and not more than 0.1 wt %. Most preferably, the concentrationshould be at least 0.6 wt % and less than 0.05 wt %. In this embodiment,higher ethylene oxide contents or higher MW tend to be less effectivefor demulsiblity. The ethylene oxide content in Pluronic L 121 is 10 wt% and average molecular weight is 4400. In a preferred embodiment, a 25wt % ethylene oxide or polyol ester and a molecular weight of 5000 wouldbe the upper limit of acceptability of an ethylene oxide or polyol esterin the demulsifier additive.

The acceptable treat ranges for the demulsifiers is at least 0.002 toless than 2.0 weight percent. A preferred treat range is at least 0.01to less than 0.1 weight percent and a most preferred treat range is 0.01and less than 0.05 weight percent.

The formulation demonstrates excellent varnish deposit properties usingthe 504 hour 120 C DRY TOST sludge test. Preferably the formulationshould be a value less than 60, more preferably a value less than 50 andmost preferably a value less than 25.

In another embodiment, we have discovered the claimed invention providesexcellent electrical conductivity (“EC”). The test used was D-4308 at32° F. A sample of liquid hydrocarbon is introduced into a cleanconductivity cell which is connected in series to a battery voltagesource and a sensitive dc ammeter. The conductivity, automaticallycalculated from the observed peak current reading dc voltage and cellconstant using Ohm's law, appears as a digital value in either a manualor automatic mode of meter operation. Low electrical conductivity canresults in static charge build up when machines are shutdown or idling.Having higher electrical conductivity can prevent a phenomena of staticdischarge which has been implicated as one root cause of varnish depositformation in gas turbines equipped with fine filtration and operating athigh flowrate. Preferably the electrical conductivity should be at least50 pS/m and more preferably at least 60 pS/m and most preferably greaterthan 100 pS/m.

In another embodiment, the formulation should have low amounts ofcalcium and zinc. The preferred embodiment is less than 5 PPM zinc andless than 5 PPM calcium. The more preferred embodiment is less than 5PPM zinc and less than 5 PPM calcium and less than 50 PPM phosphorus Aneven more preferred embodiment is less than 1 PPM zinc, less than 1 PPMcalcium and less than 5 PPM phosphorous.

A formulator skilled in the art, with the benefit of the disclosureherein would recognize the benefits of adding additional additives tothe formulation. Preferably, the formulation would comprise at least oneadditive selected form the group consisting of an antiwear additive,metal passivator, demulsifier, pour point depressant, rust inhibitor,defoamant and any combination thereof. Additional information regardingbase stocks and additives are provided below. Preferably, calciumcontaining additive, such as calcium sulfonates, would not be used duepotential reaction to form calcium carboxylate soaps with commonly usedashless rust inhibitors used in typical formulations.

Base Stocks:

Groups I, II, III, IV and V are broad categories of base oil stocksdeveloped and defined by the American Petroleum Institute (APIPublication 1509; www.API.org) to create guidelines for lubricant baseoils. Group I base stocks generally have a viscosity index of betweenabout 80 to 120 and contain greater than about 0.03% sulfur and/or lessthan about 90% saturates. Group II base stocks generally have aviscosity index of between about 80 to 120, and contain less than orequal to about 0.03% sulfur and greater than or equal to about 90%saturates. Group III stock generally has a viscosity index greater thanabout 120 and contains less than or equal to about 0.03% sulfur andgreater than about 90% saturates. Group IV includes polyalphaolefins(PAO). Group V base stocks include base stocks not included in GroupsI-IV. Table 1 summarizes properties of each of these five groups.

TABLE 1 Base Stock Properties Saturates Sulfur Viscosity Index Group I<90% and/or >0.03% and ≧80 and <120 Group II ≧90% and ≦0.03% and ≧80 and<120 Group III ≧90% and ≦0.03% and ≧120 Group IV Polyalphaolefins (PAO)Group V All other base oil stocks not included in Groups I, II, III, orIV

In a preferred embodiment, the base stocks include at least one basestock of synthetic oils and most preferably include at least one basestock of API group IV Poly Alpha Olefins. Synthetic oil for purposes ofthis application shall include all oils that are not naturally occurringmineral oils. Naturally occurring mineral oils are often referred to asAPI Group I oils.

Gas to liquid (GTL) base stocks can also be preferentially used with thecomponents of this invention as a portion or all of the base stocks usedto formulate the finished lubricant. We have discovered, favorableimprovement when the components of this invention are added tolubricating systems comprising primarily Group II, Group III and/or GTLbase stocks compared to lesser quantities of alternate fluids.

GTL materials are materials that are derived via one or more synthesis,combination, transformation, rearrangement, and/ordegradation/deconstructive processes from gaseous carbon-containingcompounds, hydrogen-containing compounds, and/or elements as feed stockssuch as hydrogen, carbon dioxide, carbon monoxide, water, methane,ethane, ethylene, acetylene, propane, propylene, propyne, butane,butylenes, and butynes. GTL base stocks and base oils are GTL materialsof lubricating viscosity that are generally derived from hydrocarbons,for example waxy synthesized hydrocarbons, that are themselves derivedfrom simpler gaseous carbon-containing compounds, hydrogen-containingcompounds and/or elements as feedstocks. GTL base stock(s) include oilsboiling in the lube oil boiling range separated/fractionated from GTLmaterials such as by, for example, distillation or thermal diffusion,and subsequently subjected to well-known catalytic or solvent dewaxingprocesses to produce lube oils of reduced/low pour point; waxisomerates, comprising, for example, hydroisomerized or isodewaxedsynthesized hydrocarbons; hydro-isomerized or isodewaxed Fischer-Tropsch(“F-T”) material (i.e., hydrocarbons, waxy hydrocarbons, waxes andpossible analogous oxygenates); preferably hydroisomerized or isodewaxedF-T hydrocarbons or hydroisomerized or isodewaxed F-T waxes,hydroisomerized or isodewaxed synthesized waxes, or mixtures thereof.

GTL base stock(s) derived from GTL materials, especially,hydroisomerized/isodewaxed F-T material derived base stock(s), and otherhydroisomerized/isodewaxed wax derived base stock(s) are characterizedtypically as having kinematic viscosities at 100° C. of from about 2mm²/s to about 50 mm²/s, preferably from about 3 mm²/s to about 50mm²/s, more preferably from about 3.5 mm²/s to about 30 mm²/s, asexemplified by a GTL base stock derived by the isodewaxing of F-T wax,which has a kinematic viscosity of about 4 mm²/s at 100° C. and aviscosity index of about 130 or greater. The term GTL base oil/basestock and/or wax isomerate base oil/base stock as used herein and in theclaims is to be understood as embracing individual fractions of GTL basestock/base oil or wax isomerate base stock/base oil as recovered in theproduction process, mixtures of two or more GTL base stocks/base oilfractions and/or wax isomerate base stocks/base oil fractions, as wellas mixtures of one or two or more low viscosity GTL base stock(s)/baseoil fraction(s) and/or wax isomerate base stock(s)/base oil fraction(s)with one, two or more high viscosity GTL base stock(s)/base oilfraction(s) and/or wax isomerate base stock(s)/base oil fraction(s) toproduce a bi-modal blend wherein the blend exhibits a viscosity withinthe aforesaid recited range. Reference herein to Kinematic Viscosityrefers to a measurement made by ASTM method D445.

GTL base stocks and base oils derived from GTL materials, especiallyhydroisomerized/isodewaxed F-T material derived base stock(s), and otherhydroisomerized/isodewaxed wax-derived base stock(s), such as waxhydroisomerates/isodewaxates, which can be used as base stock componentsof this invention are further characterized typically as having pourpoints of about −5° C. or lower, preferably about −10° C. or lower, morepreferably about −15° C. or lower, still more preferably about −20° C.or lower, and under some conditions may have advantageous pour points ofabout −25° C. or lower, with useful pour points of about −30° C. toabout −40° C. or lower. If necessary, a separate dewaxing step may bepracticed to achieve the desired pour point. References herein to pourpoint refer to measurement made by ASTM D97 and similar automatedversions.

The GTL base stock(s) derived from GTL materials, especiallyhydroisomerized/isodewaxed F-T material derived base stock(s), and otherhydroisomerized/isodewaxed wax-derived base stock(s) which are basestock components which can be used in this invention are alsocharacterized typically as having viscosity indices of 80 or greater,preferably 100 or greater, and more preferably 120 or greater.Additionally, in certain particular instances, viscosity index of thesebase stocks may be preferably 130 or greater, more preferably 135 orgreater, and even more preferably 140 or greater. For example, GTL basestock(s) that derive from GTL materials preferably F-T materialsespecially F-T wax generally have a viscosity index of 130 or greater.References herein to viscosity index refer to ASTM method D2270.

In addition, the GTL base stock(s) are typically highly paraffinic ofgreater than 90 percent saturates) and may contain mixtures ofmonocycloparaffins and multicycloparaffins in combination withnon-cyclic isoparaffins. The ratio of the naphthenic (i.e.,cycloparaffin) content in such combinations varies with the catalyst andtemperature used. Further, GTL base stocks and base oils typically havevery low sulfur and nitrogen content, generally containing less thanabout 10 ppm, and more typically less than about 5 ppm of each of theseelements. The sulfur and nitrogen content of GTL base stock and base oilobtained by the hydroisomerization/isodewaxing of F-T material,especially F-T wax is essentially nil.

In a preferred embodiment, the GTL base stock(s) comprises paraffinicmaterials that consist predominantly of non-cyclic isoparaffins and onlyminor amounts of cycloparaffins. These GTL base stock(s) typicallycomprise paraffinic materials that consist of greater than 60 wt %non-cyclic isoparaffins, preferably greater than 80 wt % non-cyclicisoparaffins, more preferably greater than 85 wt % non-cyclicisoparaffins, and most preferably greater than 90 wt % non-cyclicisoparaffins.

Useful compositions of GTL base stock(s), hydroisomerized or isodewaxedF-T material derived base stock(s), and wax-derivedhydroisomerized/isodewaxed base stock(s), such as waxisomerates/isodewaxates, are recited in U.S. Pat. Nos. 6,080,301;6,090,989, and 6,165,949 for example.

Additives:

The additives may be chosen to modify various properties of thelubricating oils. For gear oils, the additives should provide thefollowing properties, antiwear protection, rust protection, micropittingprotection, friction reduction, and improved filterability. Personsskilled in the art will recognize various additives that can be chosento achieve favorable properties including favorable properties for gearoil applications.

In various embodiments, it will be understood that additives well knownas functional fluid additives in the art, can also be incorporated inthe functional fluid composition of the invention, in relatively smallamounts, if desired; frequently, less than about 0.001% up to about10-20% or more. In one embodiment, at least one oil additive is addedfrom the group consisting of antioxidants, stabilizers, antiwearadditives, dispersants, detergents, antifoam additives, viscosity indeximprovers, copper passivators, metal deactivators, rust inhibitors,corrosion inhibitors, pour point depressants, demulsifiers, anti-wearagents, extreme pressure additives and friction modifiers. The additiveslisted below are non-limiting examples and are not intented to limit theclaims.

Dispersants should contain the alkenyl or alkyl group R has an Mn valueof about 500 to about 5000 and an Mw/Mn ratio of about 1 to about 5. Thepreferred Mn intervals depend on the chemical nature of the agentimproving filterability. Polyolefinic polymers suitable for the reactionwith maleic anhydride or other acid materials or acid forming materials,include polymers containing a predominant quantity of C2 to C5monoolefins, for example, ethylene, propylene, butylene, isobutylene andpentene. A highly suitable polyolefinic polymer is polyisobutene. Thesuccinic anhydride preferred as a reaction substance is PIBSA, that is,polyisobutenyl succinic anhydride.

If the dispersant contains a succinimide comprising the reaction productof a succinic anhydride with a polyamine, the alkenyl or alkylsubstituent of the succinic anhydride serving as the reaction substanceconsists preferably of polymerised isobutene having an Mn value of about1200 to about 2500. More advantageously, the alkenyl or alkylsubstituent of the succinic anhydride serving as the reaction substanceconsists in a polymerised isobutene having an Mn value of about 2100 toabout 2400. If the agent improving filterability contains an ester ofsuccinic acid comprising the reaction product of a succinic anhydrideand an aliphatic polyhydric alcohol, the alkenyl or alkyl substituent ofthe succinic anhydride serving as the reaction substance consistsadvantageously of a polymerised isobutene having an Mn value of 500 to1500. In preference, a polymerised isobutene having an Mn value of 850to 1200 is used.

Amides suitable uses of amines include antiwear agents, extreme pressureadditives, friction modifiers or Dispersants. The amides which areutilized in the compositions of the present invention may be amides ofmono- or polycarboxylic acids or reactive derivatives thereof. Theamides may be characterized by a hydrocarbyl group containing from about6 to about 90 carbon atoms; each is independently hydrogen or ahydrocarbyl, aminohydrocarbyl, hydroxyhydrocarbyl or aheterocyclic-substituted hydrocarbyl group, provided that both are nothydrogen; each is, independently, a hydrocarbylene group containing upto about 10 carbon atoms; Alk is an alkylene group containing up toabout 10 carbon atoms.

The amide can be derived from a monocarboxylic acid, a hydrocarbyl groupcontaining from 6 to about 30 or 38 carbon atoms and more often will bea hydrocarbyl group derived from a fatty acid containing from 12 toabout 24 carbon atoms.

The amide is derived from a di- or tricarboxylic acid, will contain from6 to about 90 or more carbon atoms depending on the type ofpolycarboxylic acid. For example, when the amide is derived from a dimeracid, will contain from about 18 to about 44 carbon atoms or more, andamides derived from trimer acids generally will contain an average offrom about 44 to about 90 carbon atoms. Each is independently hydrogenor a hydrocarbyl, aminohydrocarbyl, hydroxyhydrocarbyl or aheterocyclic-substituted hydrocarbon group containing up to about 10carbon atoms. It may be independently heterocyclic substitutedhydrocarbyl groups wherein the heterocyclic substituent is derived frompyrrole, pyrroline, pyrrolidine, morpholine, piperazine, piperidine,pyridine, pipecoline, etc. Specific examples include methyl, ethyl,n-propyl, n-butyl, n-hexyl, hydroxymethyl, hydroxyethyl, hydroxypropyl,amino-methyl, aminoethyl, aminopropyl, 2-ethylpyridine,1-ethylpyrrolidine, 1-ethylpiperidine, etc.

The alkyl group can be an alkylene group containing from 1 to about 10carbon atoms. Examples of such alkylene groups include, methylene,ethylene, propylene, etc. Also are hydrocarbylene groups, and inparticular, alkylene group containing up to about 10 carbon atoms.Examples of such hydrocarbylene groups include, methylene, ethylene,propylene, etc. The amide contains at least one morpholinyl group. Inone embodiment, the morpholine structure is formed as a result of thecondensation of two hydroxy groups which are attached to thehydrocarbylene groups. Typically, the amides are prepared by reacting acarboxylic acid or reactive derivative thereof with an amine whichcontains at least one >NH group.

Aliphatic monoamines include mono-aliphatic and di-aliphatic-substitutedamines wherein the aliphatic groups may be saturated or unsaturated andstraight chain or branched chain. Such amines include, for example,mono- and di-alkyl-substituted amines, mono- and dialkenyl-substitutedamines, etc. Specific examples of such monoamines include ethyl amine,diethyl amine, n-butyl amine, di-n-butyl amine, isobutyl amine, cocoamine, stearyl amine, oleyl amine, etc. An example of acycloaliphatic-substituted aliphatic amine is 2-(cyclohexyl)-ethylamine. Examples of heterocyclic-substituted aliphatic amines include2-(2-aminoethyl)-pyrrole, 2-(2-aminoethyl)-1-methylpyrrole,2-(2-aminoethyl)-1-methylpyrrolidine and 4-(2-aminoethyl)morpholine,1-(2-aminoethyl)piperazine, 1-(2-aminoethyl)piperidine,2-(2-aminoethyl)pyridine, 1-(2-aminoethyl)pyrrolidine,1-(3-aminopropyl)imidazole, 3-(2-aminopropyl)indole,4-(3-aminopropyl)morpholine, 1-(3-aminopropyl)-2-pipecoline,1-(3-aminopropyl)-2-pyrrolidinone, etc.

Cycloaliphatic monoamines are those monoamines wherein there is onecycloaliphatic substituent attached directly to the amino nitrogenthrough a carbon atom in the cyclic ring structure. Examples ofcycloaliphatic monoamines include cyclohexylamines, cyclopentylamines,cyclohexenylamines, cyclopentenylamines, N-ethyl-cyclohexylamine,dicyclohexylamines, and the like. Examples of aliphatic-substituted,aromatic-substituted, and heterocyclic-substituted cycloaliphaticmonoamines include propyl-substituted cyclohexyl-amines,phenyl-substituted cyclopentylamines, and pyranyl-substitutedcyclohexylamine.

Aromatic amines include those monoamines wherein a carbon atom of thearomatic ring structure is attached directly to the amino nitrogen. Thearomatic ring will usually be a mononuclear aromatic ring (i.e., onederived from benzene) but can include fused aromatic rings, especiallythose derived from naphthalene. Examples of aromatic monoamines includeaniline, di-(para-methylphenyl)amine, naphthylamine,N-(n-butyl)-aniline, and the like. Examples of aliphatic-substituted,cycloaliphatic-substituted, and heterocyclic-substituted aromaticmonoamines are para-ethoxy-aniline, para-dodecylaniline,cyclohexyl-substituted naphthylamine, phenathiazines, andthienyl-substituted aniline.

Polyamines are aliphatic, cycloaliphatic and aromatic polyaminesanalogous to the above-described monoamines except for the presencewithin their structure of additional amino nitrogens. The additionalamino nitrogens can be primary, secondary or tertiary amino nitrogens.Examples of such polyamines include N-amino-propyl-cyclohexylamines,N,N′-di-n-butyl-paraphenylene diamine, bis-(para-aminophenyl)methane,1,4-diaminocyclohexane, and the like.

The hydroxy-substituted amines contemplated are those having hydroxysubstituents bonded directly to a carbon atom other than a carbonylcarbon atom; that is, they have hydroxy groups capable of functioning asalcohols. Examples of such hydroxy-substituted amines includeethanolamine, di-(3-hydroxypropyl)-amine, 3-hydroxybutyl-amine,4-hydroxybutyl-amine, diethanolamine, di-(2-hydroxyamine,N-(hydroxypropyl)-propylamine, N-(2-methyl)-cyclohexylamine,3-hydroxycyclopentyl parahydroxyaniline, N-hydroxyethal piperazine andthe like.

In one embodiment, the amines useful in the present invention arealkylene polyamines including hydrogen, or a hydrocarbyl, aminohydrocarbyl, hydroxyhydrocarbyl or heterocyclic-substituted hydrocarbylgroup containing up to about 10 carbon atoms, Alk is an alkylene groupcontaining up to about 10 carbon atoms, and is 2 to about 10.Preferably, Alk is ethylene or propylene. Usually, a will have anaverage value of from 2 to about 7. Examples of such alkylene polyaminesinclude methylene polyamines, ethylene polyamines, butylene polyamines,propylene polyamines, pentylene polyamines, hexylene polyamines,heptylene polyamines, etc.

Alkylene polyamines include ethylene diamine, triethylene tetramine,propylene diamine, trimethylene diamine, hexamethylene diamine,decamethylene diamine, hexamethylene diamine, decamethylene diamine,octamethylene diamine, di(heptamethylene) triamine, tripropylenetetramine, tetraethylene pentamine, trimethylene diamine, pentaethylenehexamine, di(trimethylene)triamine, and the like. Higher homologs as areobtained by condensing two or more of the above-illustrated alkyleneamines are useful, as are mixtures of two or more of any of theafore-described polyamines.

Ethylene polyamines, such as those mentioned above, are especiallyuseful for reasons of cost and effectiveness. Such polyamines aredescribed in detail under the heading “Diamines and Higher Amines” inThe Encyclopedia of Chemical Technology, Second Edition, Kirk andOthmer, Volume 7, pages 27-39, Interscience Publishers, Division of JohnWiley and Sons, 1965, which is hereby incorporated by reference for thedisclosure of useful polyamines. Such compounds are prepared mostconveniently by the reaction of an alkylene chloride with ammonia or byreaction of an ethylene imine with a ring-opening reagent such asammonia, etc. These reactions result in the production of the somewhatcomplex mixtures of alkylene polyamines, including cyclic condensationproducts such as piperazines.

Other useful types of polyamine mixtures are those resulting fromstripping of the above-described polyamine mixtures. In this instance,lower molecular weight polyamines and volatile contaminants are removedfrom an alkylene polyamine mixture to leave as residue what is oftentermed “polyamine bottoms”. In general, alkylene polyamine bottoms canbe characterized as having less than 2, usually less than 1% (by weight)material boiling below about 200.degree. C. In the instance of ethylenepolyamine bottoms, which are readily available and found to be quiteuseful, the bottoms contain less than about 2% (by weight) totaldiethylene triamine (DETA) or triethylene tetramine (TETA). A typicalsample of such ethylene polyamine bottoms obtained from the Dow ChemicalCompany of Freeport, Tex. designated “E-100”. Gas chromatographyanalysis of such a sample showed it to contain about 0.93% “Light Ends”(most probably DETA), 0.72% TETA, 21.74% tetraethylene pentamine and76.61% pentaethylene hexamine and higher (by weight). These alkylenepolyamine bottoms include cyclic condensation products such aspiperazine and higher analogs of diethylene triamine, triethylenetetramine and the like.

The dispersants are selected from: Mannich bases that are condensationreaction products of a high molecular weight phenol, an alkylenepolyamine and an aldehyde such as formaldehyde, Succinic-baseddispersants that are reaction products of a olefin polymer and succinicacylating agent (acid, anhydride, ester or halide) further reacted withan organic hydroxy compound and/or an amine.

High molecular weight amides and esters such as reaction products of ahydrocarbyl acylating agent and a polyhydric aliphatic alcohol (such asglycerol, pentaerythritol or sorbitol).

Ashless (metal-free) polymeric materials that usually contain an oilsoluble high molecular weight backbone linked to a polar functionalgroup that associates with particles to be dispersed are typically usedas dispersants. Zinc acetate capped, also any treated dispersant, whichinclude borated, cyclic carbonate, end-capped, polyalkylene maleicanhydride and the like; mixtures of some of the above, in treat ratesthat range from about 0.1% up to 10-20% or more. Commonly usedhydrocarbon backbone materials are olefin polymers and copolymers, i.e.—ethylene, propylene, butylene, isobutylene, styrene; there may or maynot be further functional groups incorporated into the backbone of thepolymer, whose molecular weight ranges from 300 up to 5000. Polarmaterials such as amines, alcohols, amides or esters are attached to thebackbone via a bridge.

Antioxidants: include sterically hindered alkyl phenols such as2,6-di-tert-butylphenol, 2,6-di-tert-butyl-p-cresol and2,6-di-tert-butyl-4-(2-octyl-3-propanoic) phenol; N,N-di(alkylphenyl)amines; and alkylated phenylene-diamines.

The antioxidant component may be a hindered phenolic antioxidant such asbutylated hydroxytoluene, suitably present in an amount of 0.01 to 5%,preferably 0.4 to 0.8%, by weight of the lubricant composition.Alternatively, or in addition, component b) may comprise an aromaticamine antioxidant such as mono-octylphenylalphanapthylamine orp,p-dioctyldiphenylamine, used singly or in admixture. The amineanti-oxidant component is suitably present in a range of from 0.01 to 5%by weight of the lubricant composition, more preferably 0.5 to 1.5%.

The amine-type antioxidant includes, for example,monoalkyldiphenylamines such as monooctyldiphenylamine andmonononyldiphenylamine; dialkyldiphenylamines such as4,4′-dibutyldiphenylamine, 4,4′-dipentyldiphenylamine,4,4′-dihexyldiphenylamine, 4,4′-diheptyldiphenylamine,4,4′-dioctyldiphenylamine and 4,4′-dinonyldiphenylamine;polyalkyldiphenylamines such as tetrabutyldiphenylamine,tetrahexyldiphenylamine, tetraoctyldiphenylamine andtetranonyldiphenylamine; and naphthylamines such as.alpha.-naphthylamine, phenyl-.alpha.-naphthylamine,butylphenyl-.alpha.-naphthylamine, pentylphenyl-.alpha.-naphthylamine,hexylphenyl-.alpha.-naphthylamine, heptylphenyl-.alpha.-naphthylamine,octylphenyl-.alpha.-naphthylamine and nonylphenyl-.alpha.-naphthylamine.Of these, preferred are dialkyldiphenylamines. The sulfur-containingantioxidant and the amine-type antioxidant are added to the base oil inan amount of from 0.01 to 5% by weight, preferably from 0.03 to 3% byweight, relative to the total weight of the composition.

Oxidation inhibitors, organic compounds containing nitrogen, phosphorusand some alkylphenols are also employed. Two general types of oxidationinhibitors are those that react with the initiators, peroxy radicals,and hydroperoxides to form inactive compounds, and those that decomposethese materials to form less active compounds. Examples are hindered(alkylated) phenols, e.g. 6-di(tert-butyl)-4-methylphenol[2,6-di(tert-butyl)-p-cresol, DBPC], and aromatic amines, e.g.N-phenyl-alpha-naphthalamine. These are used in turbine, circulation,and hydraulic oils that are intended for extended service; with ratiosof amine/phenolic to be from 1:10 to 10:1 of the mixtures preferred.

Examples of phenol-based antioxidants include 2-t-butylphenol,2-t-butyl-4-methylphenol, 2-t-butyl-5-methylphenol,2,4-di-t-butylphenol, 2,4-dimethyl-6-t-butylphenol,2-t-butyl-4-methoxyphenol, 3-t-butyl-4-methoxyphenol,2,5-di-t-butylhydroquinone (manufactured by the Kawaguchi Kagaku Co.under trade designation “Antage DBH”), 2,6-di-t-butylphenol and2,6-di-t-butyl-4-alkylphenols such as 2,6-di-t-butyl-4-methylphenol and2,6-di-t-butyl-4-ethylphenol; 2,6-di-t-butyl-4-alkoxyphenols such as2,6-di-t-butyl-4-methoxyphenol and 2,6-di-t-butyl-4-ethoxyphenol,3,5-di-t-butyl-4-hydroxybenzylmercaptooctyl acetate,alkyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionates such asn-octyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate (manufactured bythe Yoshitomi Seiyaku Co. under the trade designation “Yonox SS”),n-dodecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate and2′-ethylhexyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate;2,6-di-t-butyl-.alpha.-dimethylamino-p-cresol,2,2′-methylenebis(4-alkyl-6-t-butylphenol) compounds such as2,2′-methylenebis(4-methyl-6-t-butylphenol) (manufactured by theKawaguchi Kagaku Co. under the trade designation “Antage W-400”) and2,2′-methylenebis(4-ethyl-6-t-butylphenol) (manufactured by theKawaguchi Kagaku Co. under the trade designation “Antage W-500”);bisphenols such as 4,4′-butylidenebis(3-methyl-6-t-butyl-phenol)(manufactured by the Kawaguchi Kagaku Co. under the trade designation“Antage W-300”), 4,4′-methylenebis(2,6-di-t-butylphenol) (manufacturedby Laporte Performance Chemicals under the trade designation “Ionox220AH”), 4,4′-bis(2,6-di-t-butylphenol), 2,2-(di-p-hydroxyphenyl)propane(Bisphenol A), 2,2-bis(3,5-di-t-butyl-4-hydroxyphenyl)propane,4,4′-cyclohexylidenebis(2,6-di-t-butylphenol), hexamethylene glycolbis[3, (3,5-di-t-butyl-4-hydroxyphenyl)propionate] (manufactured by theCiba Speciality Chemicals Co. under the trade designation “IrganoxL109”), triethylene glycolbis[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate] (manufactured bythe Yoshitomi Seiyaku Co. under the trade designation “Tominox 917”),2,2′-thio[diethyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate](manufactured by the Ciba Speciality Chemicals Co. under the tradedesignation “Irganox L115”),3,9-bis{1,1-dimethyl-2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)-propionyloxy]ethyl}2,4,8,10-tetraoxaspiro[5,5]undecane(manufactured by the Sumitomo Kagaku Co. under the trade designation“Sumilizer GA80”), 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane(manufactured by the Yoshitomi Seiyaku Co. under the trade designation“Yoshinox 930”),1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene(manufactured by Ciba Speciality Chemicals under the trade designation“Irganox 330”), bis[3,3′-bis(4′-hydroxy-3′-t-butylphenyl)butyric acid]glycol ester,2-(3′,5′-di-t-butyl-4-hydroxyphenyl)-methyl-4-(2″,4″-di-t-butyl-3″-hydroxyphenyl)methyl-6-t-butylphenoland 2,6-bis(2′-hydroxy-3′-t-butyl-5′-methylbenzyl)-4-methylphenol; andphenol/aldehyde condensates such as the condensates of p-t-butylphenoland formaldehyde and the condensates of p-t-butylphenol andacetaldehyde.

Viscosity index improvers and/or the pour point depressant includepolymeric alkylmethacrylates and olefinic copolymers such as anethylene-propylene copolymer or a styrene-butadiene copolymer orpolyalkene such as PIB. Viscosity index improvers (VI improvers), highmolecular weight polymers that increase the relative viscosity of an oilat high temperatures more than they do at low temperatures. The mostcommon VI improvers are methacrylate polymers and copolymers, acrylatepolymers, olefin polymers and copolymers, and styrene-butadienecopolymers.

Other examples of the viscosity index improver include polymethacrylate,polyisobutylene, alpha-olefin polymers, alpha-olefin copolymers (e.g.,an ethylene-propylene copolymer), polyalkylstyrene, phenol condensates,naphthalene condensates, a styrenebutadiene copolymer and the like. Ofthese, polymethacrylate having a number average molecular weight of10,000 to 300,000, and alpha-olefin polymers or alpha-olefin copolymershaving a number average molecular weight of 1,000 to 30,000,particularly ethylene-alpha-olefin copolymers having a number averagemolecular weight of 1,000 to 10,000 are preferred.

The viscosity index increasing agents which can be used include, forexample, polymethacrylates and ethylene/propylene copolymers, othernon-dispersion type viscosity index increasing agents such as olefincopolymers like styrene/diene copolymers, and dispersible type viscosityindex increasing agents where a nitrogen containing monomer has beencopolymerized in such materials. These materials can be added and usedindividually or in the form of mixtures, conveniently in an amountwithin the range of from 0.05 to 20 parts by weight per 100 parts byweight of base oil.

Pour point depressors (PPD): include polymethacrylates. Commonly usedadditives such as alkylaromatic polymers and polymethacrylates areuseful for this purpose; typically the treat rates range from 0.001% to1.0%.

Anti-rust additives include (short-chain) alkenyl succinic acids,partial esters thereof and nitrogen-containing derivatives thereof.Anti-rust agents include, for example, monocarboxylic acids which havefrom 8 to 30 carbon atoms, alkyl or alkenyl succinates or partial estersthereof, hydroxy-fatty acids which have from 12 to 30 carbon atoms andderivatives thereof, sarcosines which have from 8 to 24 carbon atoms andderivatives thereof, amino acids and derivatives thereof, naphthenicacid and derivatives thereof, lanolin fatty acid, mercapto-fatty acidsand paraffin oxides.

Particularly preferred anti-rust agents are indicated below. Examples ofMonocarboxylic Acids (C8-C30), Caprylic acid, pelargonic acid, decanoicacid, undecanoic acid, lauric acid, myristic acid, palmitic acid,stearic acid, arachic acid, behenic acid, cerotic acid, montanic acid,melissic acid, oleic acid, docosanic acid, erucic acid, eicosenic acid,beef tallow fatty acid, soy bean fatty acid, coconut oil fatty acid,linolic acid, linoleic acid, tall oil fatty acid, 12-hydroxystearicacid, laurylsarcosinic acid, myritsylsarcosinic acid, palmitylsarcosinicacid, stearylsarcosinic acid, oleylsarcosinic acid, alkylated (C8-C20)phenoxyacetic acids, lanolin fatty acids.

Examples of Polybasic Carboxylic Acids: The alkenyl (C10-C100) succinicacids indicated in CAS No. 27859-58-1 and ester derivatives thereof,dimer acid, N-acyl-N-alkyloxyalkyl aspartic acid esters (U.S. Pat. No.5,275,749).

Examples of the alkylamines which function as antirust addives or asreaction products with the above carboxylates to give amides and thelike are represented by primary amines such as laurylamine,coconut-amine, n-tridecylamine, myristylamine, n-pentadecylamine,palmitylamine, n-heptadecylamine, stearylamine, n-nonadecylamine,n-eicosylamine, n-heneicosylamine, n-docosylamine, n-tricosylamine,n-pentacosylamine, oleylamine, beef tallow-amine, hydrogenated beeftallow-amine and soy bean-amine. Examples of the secondary aminesinclude dilaurylamine, di-coconut-amine, di-n-tridecylamine,dimyristylamine, di-n-pentadecylamine, dipalmitylamine,di-n-pentadecylamine, distearylamine, di-n-nonadecylamine,di-n-eicosylamine, di-n-heneicosylamine, di-n-docosylamine,di-n-tricosylamine, di-n-pentacosyl-amine, dioleylamine, di-beeftallow-amine, di-hydrogenated beef tallow-amine and di-soy bean-amine.

Examples of the aforementioned N-alkylpolyalkyenediamines include:ethylenediamines such as laurylethylenediamine, coconut ethylenediamine,n-tridecylethylenediamine-, myristylethylenediamine,n-pentadecylethylenediamine, palmitylethylenediamine,n-heptadecylethylenediamine, stearylethylenediamine,n-nonadecylethylenediamine, n-eicosylethylenediamine,n-heneicosylethylenediamine, n-docosylethylendiamine,n-tricosylethylenediamine, n-pentacosylethylenediamine,oleylethylenediamine, beef tallow-ethylenediamine, hydrogenated beeftallow-ethylenediamine and soy bean-ethylenediamine; propylenediaminessuch as laurylpropylenediamine, coconut propylenediamine,n-tridecylpropylenediamine, myristylpropylenediamine,n-pentadecylpropylenediamine, palmitylpropylenediamine,n-heptadecylpropylenediamine, stearylpropylenediamine,n-nonadecylpropylenediamine, n-eicosylpropylenediamine,n-heneicosylpropylenediamine, n-docosylpropylendiamine,n-tricosylpropylenediamine, n-pentacosylpropylenediamine, diethylenetriamine (DETA) or triethylene tetramine (TETA), oleylpropylenediamine,beef tallow-propylenediamine, hydrogenated beef tallow-propylenediamineand soy bean-propylenediamine; butylenediamines such aslaurylbutylenediamine, coconut butylenediamine,n-tridecylbutylenediamine-, myristylbutylenediamine,n-pentadecylbutylenediamine, stearylbutylenediamine,n-eicosylbutylenediamine, n-heneicosylbutylenediamine,n-docosylbutylendiamine, n-tricosylbutylenediamine,n-pentacosylbutylenediamine, oleylbutylenediamine, beeftallow-butylenediamine, hydrogenated beef tallow-butylenediamine and soybean butylenediamine; and pentylenediamines such aslaurylpentylenediamine, coconut pentylenediamine,myristylpentylenediamine, palmitylpentylenediamine,stearylpentylenediamine, oleyl-pentylenediamine, beeftallow-pentylenediamine, hydrogenated beef tallow-pentylenediamine andsoy bean pentylenediamine.

Demulsifying agents: include alkoxylated phenols and phenol-formaldehyderesins and synthetic alkylaryl sulfonates such as metallicdinonylnaphthalene sulfonates. A demulsifing agent is a predominantamount of a water-soluble polyoxyalkylene glycol having a pre-selectedmolecular weight of any value in the range of between about 450 and 5000or more. An especially preferred family of water soluble polyoxyalkyleneglycol useful in the compositions of the present invention may also beone produced from alkoxylation of n-butanol with a mixture of alkyleneoxides to form a random alkoxylated product.

Functional fluids according to the invention possess a pour point ofless than about −20 degree C., and exhibit compatibility with a widerange of anti-wear additive and extreme pressure additives. Theformulations according to the invention also are devoid of fatiguefailure that is normally expected by those of ordinary skill in the artwhen dealing with polar lubricant base stocks.

Polyoxyalkylene glycols useful in the present invention may be producedby a well-known process for preparing polyalkylene oxide having hydroxylend-groups by subjecting an alcohol or a glycol ether and one or morealkylene oxide monomers such as ethylene oxide, butylene oxide, orpropylene oxide to form block copolymers in addition polymerizationwhile employing a strong base such as potassium hydroxide as a catalyst.In such process, the polymerization is commonly carried out under acatalytic concentration of 0.3 to 1.0% by mole of potassium hydroxide tothe monomer(s) and at high temperature, as 100 degrees C. to 160 degreesC. It is well known fact that the potassium hydroxide being a catalystis for the most part bonded to the chain-end of the producedpolyalkylene oxide in a form of alkoxide in the polymer solution soobtained.

An especially preferred family of soluble polyoxyalkylene glycol usefulin the compositions of the present invention may also be one producedfrom alkoxylation of n-butanol with a mixture of alkylene oxides to forma random alkoxylated product.

Foam inhibitors: include polymers of alkyl methacrylate especiallyuseful poly alkyl acrylate polymers where alkyl is generally understoodto be methyl, ethyl propyl, isopropyl, butyl, or iso butyl and polymersof dimethylsilicone which form materials called dimethylsiloxanepolymers in the viscosity range of 100 cSt to 100,000 cSt. Otheradditives are defoamers, such as silicone polymers which have been postreacted with various carbon containing moieties, are the most widelyused defoamers. Organic polymers are sometimes used as defoamersalthough much higher concentrations are required.

Metal deactivating compounds/Corrosion inhibitors: includealkyltriazoles and benzotriazoles. Examples of dibasic acids useful asanti-corrosion agents, other than sebacic acids, which may be used inthe present invention, are adipic acid, azelaic acid, dodecanedioicacid, 3-methyladipic acid, 3-nitrophthalic acid, 1,10-decanedicarboxylicacid, and fumaric acid. The anti-corrosion combination is a straight orbranch-chained, saturated or unsaturated monocarboxylic acid or esterthereof. Preferably the acid is a C sub 4 to C sub 22 straight chainunsaturated monocarboxylic acid. The preferred concentration of thisadditive is from 0.001% to 0.35% by weight of the total lubricantcomposition. However, other suitable materials are oleic acid itself;valeric acid and erucic acid. A component of the anti-corrosioncombination is a triazole as previously defined. The triazole should beused at a concentration from 0.005% to 0.25% by weight of the totalcomposition. The preferred triazole is tolylotriazole which may beincluded in the compositions of the invention include triazoles,thiazoles and certain diamine compounds which are useful as metaldeactivators or metal passivators. Examples include triazole,benzotriazole and substituted benzotriazoles such as alkyl substitutedderivatives. The alkyl substituent generally contains up to 1.5 carbonatoms, preferably up to 8 carbon atoms. The triazoles may contain othersubstituents on the aromatic ring such as halogens, nitro, amino,mercapto, etc. Examples of suitable compounds are benzotriazole and thetolyltriazoles, ethylbenzotriazoles, hexylbenzotriazoles,octylbenzotriazoles and nitrobenzotriazoles. Benzotriazole andtolyltriazole are particularly preferred. A straight or branched chainsaturated or unsaturated monocarboxylic acid which is optionallysulphurised in an amount which may be up to 35% by weight; or an esterof such an acid; and a triazole or alkyl derivatives thereof, or shortchain alkyl of up to 5 carbon atoms; n is zero or an integer between 1and 3 inclusive; and is hydrogen, morpholino, alkyl, amido, amino,hydroxy or alkyl or aryl substituted derivatives thereof, or a triazoleselected from 1,2,4 triazole, 1,2,3 triazole,5-anilo-1,2,3,4-thiatriazole, 3-amino-1,2,4 triazole,1-H-benzotriazole-1-yl-methylisocyanide, methylene-bis-benzotriazole andnaphthothiazole.

Alkyl is straight or branched chain and is for example methyl, ethyl,n-propyl, iso-propyl, n-butyl, sec-butyl, n-pentyl, n-hexyl, n-heptyl,n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-dodecyl, n-tetradecyl,n-hexadecyl, n-octadecyl or n-eicosyl.

Alkenyl is straight or branched chain and is for example prop-2-enyl,but-2-enyl, 2-methyl-prop-2-enyl, pent-2-enyl, hexa-2,4-dienyl,dec-10-enyl or eicos-2-enyl. Cylcoalkyl is for example cyclopentyl,cyclohexyl, cyclooctyl, cyclodecyl, adamantyl or cyclododecyl. Aralkylis for example benzyl, 2-phenylethyl, benzhydryl or naphthylmethyl.

Aryl is for example phenyl or naphthyl. The heterocyclic group is forexample a morpholine, pyrrolidine, piperidine or a perhydroazepine ring.Alkylene moieties include for example methylene, ethylene, 1:2- or1:3-propylene, 1:4-butylene, 1:6-hexylene, 1:8-octylene, 1:10-decyleneand 1:12-dodecylene.

Arylene moieties include for example phenylene and naphthylene. 1-(or4)-(dimethylaminomethyl) triazole, 1-(or 4)-(diethylaminomethyl)triazole, 1-(or 4)-(di-isopropylaminomethyl) triazole, 1-(or4)-(di-n-butylaminomethyl) triazole, 1-(or 4)-(di-n-hexylaminomethyl)triazole, 1-(or 4)-(di-isooctylaminomethyl) triazole, 1-(or4)-(di-(2-ethylhexyl)aminomethyl) triazole, 1-(or4)-(di-n-decylaminomethyl) triazole, 1-(or 4)-(di-n-dodecylaminomethyl)triazole, 1-(or 4)-(di-n-octadecylaminomethyl) triazole, 1-(or4)-(di-n-eicosylaminomethyl) triazole, 1-(or4)-[di-(prop-2′-enyl)aminomethyl] triazole, 1-(or4)-[di-(but-2′-enyl)aminomethyl] triazole, 1-(or4)-[di-(eicos-2′-enyl)aminomethyl] triazole, 1-(or4)-(di-cyclohexylaminomethyl) triazole, 1-(or 4)-(di-benzylaminomethyl)triazole, 1-(or 4)-(di-phenylaminomethyl) triazole, 1-(or4)-(4′-morpholinomethyl) triazole, 1-(or 4)-(1′-pyrrolidinomethyl)triazole, 1-(or 4)-(1′-piperidinomethyl) triazole, 1-(or4)-(1′-perhydroroazepinomethyl) triazole, 1-(or4)-(2′,2″-dihydroxyethyl)aminomethyl] triazole, 1-(or4)-(dibutoxypropyl-aminomethyl) triazole, 1-(or4)-(dibutylthiopropyl-aminomethyl) triazole, 1-(or4)-(di-butylaminopropyl-aminomethyl) triazole, 1-(or-4)-(1-methanomine)-N,N-bis(2-ethylhexyl)-methyl benzotriazole,N,N-bis-(1- or 4-triazolylmethyl) laurylamine, N,N-bis-(1- or4-triazolylmethyl) oleylamine, N,N-bis-(1- or4-triazolylmethyl)ethanolamine and N,N,N′,N′-tetra(1- or4-triazolylmethyl)ethylene diamine.

The metal deactivating agents which can be used in the lubricating oil acomposition of the present invention include benzotriazole and the4-alkylbenzotriazoles such as 4-methylbenzotriazole and4-ethylbenzotriazole; 5-alkylbenzotriazoles such as5-methylbenzotriazole, 5-ethylbenzotriazole; 1-alkylbenzotriazoles suchas 1-dioctylauainomethyl-2,3-benzotriazole; benzotriazole derivativessuch as the 1-alkyltolutriazoles, for example,1-dioctylaminomethyl-2,3-tolutriazole; benzimidazole and benzimidazolederivatives or concentrates and/or mixtures thereof.

Anti-wear agents/Extreme pressure agent/Friction Reducer: arylphosphates and phosphites, and metal or ash-free carbamates. A phosphateester or salt may be a monohydrocarbyl, dihydrocarbyl or atrihydrocarbyl phosphate, wherein each hydrocarbyl group is saturated.In one embodiment, each hydrocarbyl group independently contains fromabout 8 to about 30, or from about 12 up to about 28, or from about 14up to about 24, or from about 14 up to about 18 carbons atoms. In oneembodiment, the hydrocarbyl groups are alkyl groups. Examples ofhydrocarbyl groups include tridecyl, tetradecyl, pentadecyl, hexadecyl,heptadecyl, octadecyl groups and mixtures thereof.

A phosphate ester or salt is a phosphorus acid ester prepared byreacting one or more phosphorus acid or anhydride with a saturatedalcohol. The phosphorus acid or anhydride is generally an inorganicphosphorus reagent, such as phosphorus pentoxide, phosphorus trioxide,phosphorus tetroxide, phosphorous acid, phosphoric acid, phosphorushalide, lower phosphorus esters, or a phosphorus sulfide, includingphosphorus pentasulfide, and the like. Lower phosphorus acid estersgenerally contain from 1 to about 7 carbon atoms in each ester group.Alcohols used to prepare the phosphorus acid esters or salts. Examplesof commercially available alcohols and alcohol mixtures include Alfol1218 (a mixture of synthetic, primary, straight-chain alcoholscontaining 12 to 18 carbon atoms); Alfol 20+ alcohols (mixtures of C18-C 28 primary alcohols having mostly C20 alcohols as determined by GLC(gas-liquid-chromatography)); and Alfol22+ alcohols (C 18-C 28 primaryalcohols containing primarily C 22 alcohols). Alfol alcohols areavailable from Continental Oil Company. Another example of acommercially available alcohol mixture is Adol 60 (about 75% by weightof a straight chain C 22 primary alcohol, about 15% of a C 20 primaryalcohol and about 8% of C 18 and C 24 alcohols). The Adol alcohols aremarketed by Ashland Chemical.

A variety of mixtures of monohydric fatty alcohols derived fromnaturally occurring triglycerides and ranging in chain length from C 8to C 18 are available from Procter & Gamble Company. These mixturescontain various amounts of fatty alcohols containing 12, 14, 16, or 18carbon atoms. For example, CO-1214 is a fatty alcohol mixture containing0.5% of C 10 alcohol, 66.0% of C 12 alcohol, 26.0% of C 14 alcohol and6.5% of C 16 alcohol.

Another group of commercially available mixtures include the “Neodol”products available from Shell Chemical Co. For example, Neodol 23 is amixture of C 12 and C 13 alcohols; Neodol 25 is a mixture of C 12 to C15 alcohols; and Neodol 45 is a mixture of C 14 to C 15 linear alcohols.The phosphate contains from about 14 to about 18 carbon atoms in eachhydrocarbyl group. The hydrocarbyl groups of the phosphate are generallyderived from a mixture of fatty alcohols having from about 14 up toabout 18 carbon atoms. The hydrocarbyl phosphate may also be derivedfrom a fatty vicinal diol. Fatty vicinal diols include those availablefrom Ashland Oil under the general trade designation Adol 114 and Adol158. The former is derived from a straight chain alpha olefin fractionof C 11-C 14, and the latter is derived from a C 15-C 18 fraction.

The phosphate salts may be prepared by reacting an acidic phosphateester with an amine compound or a metallic base to form an amine or ametal salt. The amines may be monoamines or polyamines. Useful aminesinclude those amines disclosed in U.S. Pat. No. 4,234,435.

The monoamines generally contain a hydrocarbyl group which contains from1 to about 30 carbon atoms, or from 1 to about 12, or from 1 to about 6.Examples of primary monoamines useful in the present invention includemethylamine, ethylamine, propylamine, butylamine, cyclopentylamine,cyclohexylamine, octylamine, dodecylamine, allylamine, cocoamine,stearylamine, and laurylamine. Examples of secondary monoamines includedimethylamine, diethylamine, dipropylamine, dibutylamine,dicyclopentylamine, dicyclohexylamine, methylbutylamine,ethylhexylamine, etc.

An amine is a fatty (C.sub.8-30) amine which includes n-octylamine,n-decylamine, n-dodecylamine, n-tetradecylamine, n-hexadecylamine,n-octadecylamine, oleyamine, etc. Also useful fatty amines includecommercially available fatty amines such as “Armeen” amines (productsavailable from Akzo Chemicals, Chicago, Ill.), such Armeen C, Armeen O,Armeen OL, Armeen T, Armeen HT, Armeen S and Armeen SD, wherein theletter designation relates to the fatty group, such as coco, oleyl,tallow, or stearyl groups.

Other useful amines include primary ether amines, such as thoserepresented by the formula, R″(OR′) x NH 2, wherein R′ is a divalentalkylene group having about 2 to about 6 carbon atoms; x is a numberfrom one to about 150, or from about one to about five, or one; and R″is a hydrocarbyl group of about 5 to about 150 carbon atoms. An exampleof an ether amine is available under the name SURFAM® amines producedand marketed by Mars Chemical Company, Atlanta, Ga. Preferredetheramines are exemplified by those identified as SURFAM P14B(decyloxypropylamine), SURFAM P16A (linear C 16), SURFAM P17B(tridecyloxypropylamine). The carbon chain lengths (i.e., C 14, etc.) ofthe SURFAMS described above and used hereinafter are approximate andinclude the oxygen ether linkage.

An amine is a tertiary-aliphatic primary amine. Generally, the aliphaticgroup, preferably an alkyl group, contains from about 4 to about 30, orfrom about 6 to about 24, or from about 8 to about 22 carbon atoms.Usually the tertiary alkyl primary amines are monoamines the alkyl groupis a hydrocarbyl group containing from one to about 27 carbon atoms andR 6 is a hydrocarbyl group containing from 1 to about 12 carbon atoms.Such amines are illustrated by tert-butylamine, tert-hexylamine,1-methyl-1-amino-cyclohexane, tert-octylamine, tert-decylamine,tert-dodecylamine, tert-tetradecylamine, tert-hexadecylamine,tert-octadecylamine, tert-tetracosanylamine, and tert-octacosanylamine.Mixtures of tertiary aliphatic amines may also be used in preparing thephosphate salt. Illustrative of amine mixtures of this type are “Primene81R” which is a mixture of C 11-C 14 tertiary alkyl primary amines and“Primene JMT” which is a similar mixture of C 18-C 22 tertiary alkylprimary amines (both are available from Rohm and Haas Company). Thetertiary aliphatic primary amines and methods for their preparation areknown to those of ordinary skill in the art. The tertiary aliphaticprimary amine useful for the purposes of this invention and methods fortheir preparation are described in U.S. Pat. An amine is a heterocyclicpolyamine. The heterocyclic polyamines include aziridines, azetidines,azolidines, tetra- and dihydropyridines, pyrroles, indoles, piperidines,imidazoles, di- and tetra-hydroimidazoles, piperazines, isoindoles,purines, morpholines, thiomorpholines, N-aminoalkylmorpholines,N-aminoalkylthiomorpholines, N-aminoalkyl-piperazines,N,N′-diaminoalkylpiperazines, azepines, azocines, azonines, azecines andtetra-, di- and perhydro derivatives of each of the above and mixturesof two or more of these heterocyclic amines. Preferred heterocyclicamines are the saturated 5- and 6-membered heterocyclic aminescontaining only nitrogen, oxygen and/or sulfur in the hetero ring,especially the piperidines, piperazines, thiomorpholines, morpholines,pyrrolidines, and the like. Piperidine, aminoalkyl substitutedpiperidines, piperazine, aminoalkyl substituted piperazines, morpholine,aminoalkyl substituted morpholines, pyrrolidine, andaminoalkyl-substituted pyrrolidines, are especially preferred. Usuallythe aminoalkyl substituents are substituted on a nitrogen atom formingpart of the hetero ring. Specific examples of such heterocyclic aminesinclude N-aminopropylmorpholine, N-aminoethylpiperazine, andN,N′-diaminoethylpiperazine. Hydroxy heterocyclic polyamines are alsouseful. Examples include N-(2-hydroxyethyl)cyclohexylamine,3-hydroxycyclopentylamine, parahydroxyaniline, N-hydroxyethylpiperazine,and the like.

Lubricating compositions also may include a fatty imidazoline or areaction product of a fatty carboxylic acid and at least one polyamine.The fatty imidazoline has fatty substituents containing from 8 to about30, or from about 12 to about 24 carbon atoms. The substituent may besaturated or unsaturated, heptadecenyl derived oleyl groups, preferablysaturated. In one aspect, the fatty imidazoline may be prepared byreacting a fatty carboxylic acid with a polyalkylenepolyamine, such asthose discussed above. The fatty carboxylic acids are generally mixturesof straight and branched chain fatty carboxylic acids containing about 8to about 30 carbon atoms, or from about 12 to about 24, or from about 16to about 18. Carboxylic acids include the polycarboxylic acids orcarboxylic acids or anhydrides having from 2 to about 4 carbonyl groups,preferably 2. The polycarboxylic acids include succinic acids andanhydrides and Diels-Alder reaction products of unsaturatedmonocarboxylic acids with unsaturated carboxylic acids (such as acrylic,methacrylic, maleic, fumaric, crotonic and itaconic acids). Preferably,the fatty carboxylic acids are fatty monocarboxylic acids, having fromabout 8 to about 30, preferably about 12 to about 24 carbon atoms, suchas octanoic, oleic, stearic, linoleic, dodecanoic, and tall oil acids,preferably stearic acid. The fatty carboxylic acid is reacted with atleast one polyamine. The polyamines may be aliphatic, cycloaliphatic,heterocyclic or aromatic. Examples of the polyamines include alkylenepolyamines and heterocyclic polyamines.

Hydroxyalkyl groups are to be understood as meaning, for example,monoethanolamine, diethanolamine or triethanolamine, and the term aminealso includes diamine. The amine used for the neutralization depends onthe phosphoric esters used. The EP additive according to the inventionhas the following advantages: It very high effectiveness when used inlow concentrations and it is free of chlorine. For the neutralization ofthe phosphoric esters, the latter are taken and the corresponding amineslowly added with stirring. The resulting heat of neutralization isremoved by cooling. The EP additive according to the invention can beincorporated into the respective base liquid with the aid of fattysubstances (e.g. tall oil fatty acid, oleic acid, etc.) as solubilizers.The base liquids used are napthenic or paraffinic base oils, syntheticoils (e.g. polyglycols, mixed polyglycols), polyolefins, carboxylicesters, etc.

The composition comprises at least one phosphorus containing extremepressure additive. Examples of such additives are amine phosphateextreme pressure additives such as that known under the trade nameIRGALUBE 349 Such amine phosphates are suitably present in an amount offrom 0.01 to 2%, preferably 0.2 to 0.6% by weight of the lubricantcomposition.

At least one straight and/or branched chain saturated or unsaturatedmonocarboxylic acid which is optionally sulphurised in an amount whichmay be up to 35% by weight; and/or an ester of such an acid. At leastone triazole or alkyl derivatives thereof, or short chain alkyl of up to5 carbon atoms and is hydrogen, morphilino, alkyl, amido, amino, hydroxyor alkyl or aryl substituted derivatives thereof; or a triazole selectedfrom 1,2,4 triazole, 1,2,3 triazole, 3-amino-1,2,4 triazole,1-H-benzotriazole-1-yl-methylisocyanide, methylene-bis-benzotriazole andnaphthotriazole; and The neutral organic phosphate which forms acomponent of the formulation may be present in an amount of 0.01 to 4%,preferably 1.5 to 2.5% by weight of the composition. The above aminephosphates and any of the aforementioned benzo- or tolyltriazoles can bemixed together to form a single component capable of delivering antiwearperformance. The neutral organic phosphate is also a conventionalingredient of lubricating compositions and any such neutral organicphosphate falling within the formula as previously defined may beemployed.

Phosphates for use in the present invention include phosphates, acidphosphates, phosphites and acid phosphites. The phosphates includetriaryl phosphates, trialkyl phosphates, trialkylaryl phosphates,triarylalkyl phosphates and trialkenyl phosphates. As specific examplesof these, referred to are triphenyl phosphate, tricresyl phosphate,benzyldiphenyl phosphate, ethyldiphenyl phosphate, tributyl phosphate,ethyldibutyl phosphate, cresyldiphenyl phosphate, dicresylphenylphosphate, ethylphenyldiphenyl phosphate, diethylphenylphenyl phosphate,propylphenyldiphenyl phosphate, dipropylphenylphenyl phosphate,triethylphenyl phosphate, tripropylphenyl phosphate, butylphenyldiphenylphosphate, dibutylphenylphenyl phosphate, tributylphenyl phosphate,trihexyl phosphate, tri(2-ethylhexyl) phosphate, tridecyl phosphate,trilauryl phosphate, trimyristyl phosphate, tripalmityl phosphate,tristearyl phosphate, and trioleyl phosphate. The acid phosphatesinclude, for example, 2-ethylhexyl acid phosphate, ethyl acid phosphate,butyl acid phosphate, oleyl acid phosphate, tetracosyl acid phosphate,isodecyl acid phosphate, lauryl acid phosphate, tridecyl acid phosphate,stearyl acid phosphate, and isostearyl acid phosphate.

The phosphites include, for example, triethyl phosphite, tributylphosphite, triphenyl phosphite, tricresyl phosphite, tri(nonylphenyl)phosphite, tri(2-ethylhexyl) phosphite, tridecyl phosphite, trilaurylphosphite, triisooctyl phosphite, diphenylisodecyl phosphite, tristearylphosphite, and trioleyl phosphite.

The acid phosphites include, for example, dibutyl hydrogenphosphite,dilauryl hydrogenphosphite, dioleyl hydrogenphosphite, distearylhydrogenphosphite, and diphenyl hydrogenphosphite. Amines that formamine salts with such phosphates include, for example, mono-substitutedamines, di-substituted amines and tri-substituted amines. Examples ofthe mono-substituted amines include butylamine, pentylamine, hexylamine,cyclohexylamine, octylamine, laurylamine, stearylamine, oleylamine andbenzylamine; and those of the di-substituted amines include dibutylamine, dipentylamine, dihexylamine, dicyclohexylamine, dioctylamine,dilaurylamine, distearylamine, dioleylamine, dibenzylamine, stearylmonoethanolamine, decyl monoethanolamine, hexyl monopropanolamine,benzyl monoethanolamine, phenyl monoethanolamine, and tolylmonopropanolamine. Examples of tri-substituted amines includetributylamine, tripentylamine, trihexylamine, tricyclohexylamine,trioctylamine, trilaurylamine, tristearylamine, trioleylamine,tribenzylamine, dioleyl monoethanolamine, dilauryl monopropanolamine,dioctyl monoethanolamine, dihexyl monopropanolamine, dibutylmonopropanolamine, oleyl diethanolamine, stearyl dipropanolamine, lauryldiethanolamine, octyl dipropanolamine, butyl diethanolamine, benzyldiethanolamine, phenyl diethanolamine, tolyl dipropanolamine, xylyldiethanolamine, triethanolamine, and tripropanolamine.

Phosphates or their amine salts are added to the base oil in an amountof from 0.03 to 5% by weight, preferably from 0.1 to 4% by weight,relative to the total weight of the composition. Carboxylic acids to bereacted with amines include, for example, aliphatic carboxylic acids,dicarboxylic acids (dibasic acids), and aromatic carboxylic acids. Thealiphatic carboxylic acids have from 8 to 30 carbon atoms, and may besaturated or unsaturated, and linear or branched. Specific examples ofthe aliphatic carboxylic acids include pelargonic acid, lauric acid,tridecanoic acid, myristic acid, palmitic acid, stearic acid, isostearicacid, eicosanoic acid, behenic acid, triacontanoic acid, caproleic acid,undecylenic acid, oleic acid, linolenic acid, erucic acid, and linoleicacid. Specific examples of the dicarboxylic acids includeoctadecylsuccinic acid, octadecenylsuccinic acid, adipic acid, azelaicacid, and sebacic acid. One example of the aromatic carboxylic acids issalicylic acid. The amines to be reacted with carboxylic acids include,for example, polyalkylene-polyamines such as diethylenetriamine,triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine,hexaethyleneheptamine, heptaethyleneoctamine, dipropylenetriamine,tetrapropylenepentamine, and hexabutyleneheptamine; and alkanolaminessuch as monoethanolamine and diethanolamine. Of these, preferred are acombination of isostearic acid and tetraethylenepentamine, and acombination of oleic acid and diethanolamine. The reaction products ofcarboxylic acids and amines are added to the base oil in an amount offrom 0.01 to 5% by weight, preferably from 0.03 to 3% by weight,relative to the total weight of the composition.

Important components are phosphites. As used herein, the term“hydrocarbyl substituent” or “hydrocarbyl group” is used in its ordinarysense, which is well-known to those skilled in the art. Specifically, itrefers to a group having a carbon atom directly attached to theremainder of the molecule and having predominantly hydrocarboncharacter. Examples of hydrocarbyl groups include: Hydrocarbonsubstituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic(e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-,aliphatic-, and alicyclic-substituted aromatic substituents, as well ascyclic substituents wherein the ring is completed through anotherportion of the molecule (e.g., two substituents together form analicyclic radical); The substituted hydrocarbon substituents, that is,substituents containing non-hydrocarbon groups which, in the context ofthis invention, do not alter the predominantly hydrocarbon substituent,hydroxy, alkoxy, nitro); Hetero-atom containing substituents, that is,substituents which, while having a predominantly hydrocarbon character,in the context of this invention, contain other than carbon in a ring orchain otherwise composed of carbon atoms. Heteroatoms include sulfur,oxygen, nitrogen, and encompass substituents as pyridyl, furyl, thienyland imidazolyl. In general, no more than two, preferably no more thanone, non-hydrocarbon substituent will be present for every ten carbonatoms in the hydrocarbyl group; typically, there will be nonon-hydrocarbon substituents in the hydrocarbyl group.

The term “hydrocarbyl group,” in the context of the present invention,is also intended to encompass cyclic hydrocarbyl or hydrocarbylenegroups, where two or more of the alkyl groups in the above structurestogether form a cyclic structure. The hydrocarbyl or hydrocarbylenegroups of the present invention generally are alkyl or cycloalkyl groupswhich contain at least 3 carbon atoms. Preferably or optimallycontaining sulfur, nitrogen, or oxygen, they will contain 4 to 24, andalternatively 5 to 18 carbon atoms. In another embodiment they containabout 6, or exactly 6 carbon atoms. The hydrocarbyl groups can betertiary or preferably primary or secondary groups; in one embodimentthe component is a di(hydrocarbyl)hydrogen phosphite and each of thehydrocarbyl groups is a primary alkyl group; in another embodiment thecomponent is a di(hydrocarbyl)hydrogen phosphite and each of thehydrocarbyl groups is a secondary alkyl group. In yet another embodimentthe component is a hydrocarbylenehydrogen phosphite.

Examples of straight chain hydrocarbyl groups include methyl, ethyl,n-propyl, n-butyl, n-hexyl, n-octyl, n-decyl, n-dodecyl, n-tetradecyl,stearyl, n-hexadecyl, n-octadecyl, oleyl, and cetyl. Examples ofbranched-chain hydrocarbon groups include isopropyl, isobutyl, secondarybutyl, tertiary butyl, neopentyl, 2-ethylhexyl, and 2,6-dimethylheptyl.Examples of cyclic groups include cyclobutyl, cyclopentyl,methylcyclopentyl, cyclohexyl, methylcyclohexyl, cycloheptyl, andcyclooctyl. A few examples of aromatic hydrocarbyl groups and mixedaromatic-aliphatic hydrocarbyl groups include phenyl, methylphenyl,tolyl, and naphthyl.

The R groups can also comprise a mixture of hydrocarbyl groups derivedfrom commercial alcohols. Examples of some monohydric alcohols andalcohol mixtures include the commercially available “Alfol™” alcoholsmarketed by Continental Oil Corporation. Alfol™ 810, for instance, is amixture containing alcohols consisting essentially of straight chain,primary alcohols having from 8 to 12 carbon atoms. Alfol™ 12 is amixture of mostly C12 fatty alcohols; Alfol™ 22+ comprises C 18-28primary alcohols having mostly C 22 alcohols, and so on. Variousmixtures of monohydric fatty alcohols derived from naturally occurringtriglycerides and ranging in chain length from C 8 to C 18 are availablefrom Procter & Gamble Company. “Neodol™” alcohols are available fromShell Chemical Co., where, for instance, Neodol™ 25 is a mixture of C 12to C 15 alcohols.

Specific examples of some of the phosphites within the scope of theinvention include phosphorous acid, mono-, di-, or tri-propyl phosphite;mono-, di-, or tri-butyl phosphite, di-, or tri-amyl phosphite; mono-,di-, or tri-hexyl phosphite; mono-, di-, or tri-phenyl; mono-, di-, ortri-tolyl phosphite; mono-, di-, or tri-cresyl phosphite; dibutyl phenylphosphite or mono-, di-, or tri-phosphite, amyl dicresyl phosphite.

The phosphorus compounds of the present invention are prepared by wellknown reactions. One route the reaction of an alcohol or a phenol withphosphorus trichloride or by a transesterification reaction. Alcoholsand phenols can be reacted with phosphorus pentoxide to provide amixture of an alkyl or aryl phosphoric acid and a dialkyl or diarylphosphoric acid. Alkyl phosphates can also be prepared by the oxidationof the corresponding phosphites. In any case, the reaction can beconducted with moderate heating. Moreover, various phosphorus esters canbe prepared by reaction using other phosphorus esters as startingmaterials. Thus, medium chain (C9 to C22) phosphorus esters have beenprepared by reaction of dimethylphosphite with a mixture of medium-chainalcohols by means of a thermal transesterification or an acid- orbase-catalyzed transesterification; see for example U.S. Pat. No.4,652,416. Most such materials are also commercially available; forinstance, triphenyl phosphite is available from Albright and Wilson asDuraphos TPP™; di-n-butyl hydrogen phosphite from Albright and Wilson asDuraphos DBHP™; and triphenylthiophosphate from Ciba Specialty Chemicalsas Irgalube TPPT™.

The other major component of the present composition is a hydrocarbonhaving ethylenic unsaturation. This would normally be described as anolefin or a diene, triene, polyene, and so on, depending on the numberof ethylenic unsaturations present. Preferably the olefin is monounsaturated, that is, containing only a single ethylenic double bond permolecule. The olefin can be a cyclic or a linear olefin. If a linearolefin, it can be an internal olefin or an alpha-olefin. The olefin canalso contain aromatic unsaturation, i.e., one or more aromatic rings,provided that it also contains ethylenic (non-aromatic) unsaturation.

The olefin normally will contain 6 to 30 carbon atoms. Olefins havingsignificantly fewer than 6 carbon atoms tend to be volatile liquids orgases which are not normally suitable for formulation into a compositionsuitable as an antiwear lubricant. Preferably the olefin will contain 6to 18 or 6 to 12 carbon atoms, and alternatively 6 or 8 carbon atoms.

Among suitable olefins are alkyl-substituted cyclopentenes, hexenes,cyclohexene, alkyl-substituted cyclohexenes, heptenes, cycloheptenes,alkyl-substituted cycloheptenes, octenes including diisobutylene,cyclooctenes, alkyl-substituted cyclooctenes, nonenes, decenes,undecenes, dodecenes including propylene tetramer, tridecenes,tetradecenes, pentadecenes, hexadecenes, heptadecenes, octadecenes,cyclooctadiene, norbornene, dicyclopentadiene, squalene,diphenylacetylene, and styrene. Highly preferred olefins are cyclohexeneand 1-octene.

The mixtures of alcohols may be mixtures of different primary alcohols,mixtures of different secondary alcohols or mixtures of primary andsecondary alcohols. Examples of useful mixtures include: n-butanol andn-octanol; n-pentanol and 2-ethyl-1-hexanol; isobutanol and n-hexanol;isobutanol and isoamyl alcohol; isopropanol and 2-methyl-4-pentanol;isopropanol and sec-butyl alcohol; isopropanol and isooctyl alcohol; andthe like.

Organic triesters of phosphorus acids are also employed in lubricants.Typical esters include triarylphosphates, trialkyl phosphates, neutralalkylaryl phosphates, alkoxyalkyl phosphates, triaryl phosphite,trialkylphosphite, neutral alkyl aryl phosphites, neutral phosphonateesters and neutral phosphine oxide esters. In one embodiment, the longchain dialkyl phosphonate esters are used. More preferentially, thedimethyl-, diethyl-, and dipropyl-oleyl phosphonates can be used.Neutral acids of phosphorus acids are the triesters rather than an acid(HO—P) or a salt of an acid.

Any C4 to C8 alkyl or higher phosphate ester may be employed in theinvention. For example, tributyl phosphate (TBP) and tri isooctalphosphate (TOF) can be used. The specific triphosphate ester orcombination of esters can easily be selected by one skilled in the artto adjust the density, viscosity etc. of the formulated fluid. Mixedesters, such as dibutyl octyl phosphate or the like may be employedrather than a mixture of two or more trialkyl phosphates.

A trialkyl phosphate is often useful to adjust the specific gravity ofthe formulation, but it is desirable that the specific trialkylphosphate be a liquid at low temperatures. Consequently, a mixed estercontaining at least one partially alkylated with a C3 to C4 alkyl groupis very desirable, for example, 4-isopropylphenyl diphenyl phosphate or3-butylphenyl diphenyl phosphate. Even more desirable is a triarylphosphate produced by partially alkylating phenol with butylene orpropylene to form a mixed phenol which is then reacted with phosphorusoxychloride as taught in U.S. Pat. No. 3,576,923.

Any mixed triaryl phosphate (TAP) esters may be used as cresyl diphenylphosphate, tricresyl phosphate, mixed xylyl cresyl phosphates, loweralkylphenyl/phenyl phosphates, such as mixed isopropylphenyl/phenylphosphates, t-butylphenyl phenyl phosphates. These esters are usedextensively as plasticizers, functional fluids, gasoline additives,flame-retardant additives and the like.

The phosphoric acid ester, thiophosphoric acid ester, and amine saltthereof functions to enhance the lubricating performances, and can beselected from known compounds conventionally employed as extremepressure agents. Generally employed are phosphoric acid esters, or anamine salt thereof which has an alkyl group, an alkenyl group, analkylaryl group, or an aralkyl group, any of which containsapproximately 3 to 30 carbon atoms.

Examples of the phosphoric acid esters include aliphatic phosphoric acidesters such as triisopropyl phosphate, tributyl phosphate, ethyl dibutylphosphate, trihexyl phosphate, tri-2-ethylhexyl phosphate, trilaurylphosphate, tristearyl phosphate, and trioleyl phosphate; and aromaticphosphoric acid esters such as benzyl phenyl phosphate, allyl diphenylphosphate, triphenyl phosphate, tricresyl phosphate, ethyl diphenylphosphate, cresyl diphenyl phosphate, dicresyl phenyl phosphate,ethylphenyl diphenyl phosphate, diethylphenyl phenyl phosphate,propylphenyl diphenyl phosphate, dipropylphenyl phenyl phosphate,triethylphenyl phosphate, tripropylphenyl phosphate, butylphenyldiphenyl phosphate, dibutylphenyl phenyl phosphate, and tributylphenylphosphate. Preferably, the phosphoric acid ester is a trialkylphenylphosphate.

Also employable are amine salts of the above-mentioned phosphates. Aminesalts of acidic alkyl or aryl esters of the phosphoric acid andthiophosphoric acid are also employable. Preferably, the amine salt isan amine salt of trialkylphenyl phosphate or an amine salt of alkylphosphate.

One or any combination of the compounds selected from the groupconsisting of a phosphoric acid ester, and an amine salt thereof may beused. The phosphorus acid ester and/or its amine salt function toenhance the lubricating performances, and can be selected from knowncompounds conventionally employed as extreme pressure agents. Generallyemployed are a phosphorus acid ester or an amine salt thereof which hasan alkyl group, an alkenyl group, an alkylaryl group, or an aralkylgroup, any of which contains approximately 3 to 30 carbon atoms.

Examples of the phosphorus acid esters include aliphatic phosphorus acidesters such as triisopropyl phosphite, tributyl phosphite, ethyl dibutylphosphite, trihexyl phosphite, tri-2-ethylhexylphosphite, trilaurylphosphite, tristearyl phosphite, and trioleyl phosphite; and aromaticphosphorus acid esters such as benzyl phenyl phosphite, allyldiphenylphosphite, triphenyl phosphite, tricresyl phosphite, ethyldiphenyl phosphite, tributyl phosphite, ethyl dibutyl phosphite, cresyldiphenyl phosphite, dicresyl phenyl phosphite, ethylphenyl diphenylphosphite, diethylphenyl phenyl phosphite, propylphenyl diphenylphosphite, dipropylphenyl phenyl phosphite, triethylphenyl phosphite,tripropylphenyl phosphite, butylphenyl diphenyl phosphite, dibutylphenylphenyl phosphite, and tributylphenyl phosphite. Also favorably employedare dilauryl phosphite, dioleyl phosphite, dialkyl phosphites, anddiphenyl phosphite. Preferably, the phosphorus acid ester is a dialkylphosphite or a trialkyl phosphite.

The phosphate salt may be derived from a polyamine. The polyaminesinclude alkoxylated diamines, fatty polyamine diamines,alkylenepolyamines, hydroxy containing polyamines, condensed polyaminesarylpolyamines, and heterocyclic polyamines. Commercially availableexamples of alkoxylated diamines include those amine where y in theabove formula is one. Examples of these amines include Ethoduomeen T/13and T/20 which are ethylene oxide condensation products ofN-tallowtrimethylenediamine containing 3 and 10 moles of ethylene oxideper mole of diamine, respectively.

In another embodiment, the polyamine is a fatty diamine. The fattydiamines include mono- or dialkyl, symmetrical or asymmetrical ethylenediamines, propane diamines (1,2, or 1,3), and polyamine analogs of theabove. Suitable commercial fatty polyamines are Duomeen C.(N-coco-1,3-diaminopropane), Duomeen S(N-soya-1,3-diaminopropane),Duomeen T (N-tallow-1,3-diaminopropane), and Duomeen 0(N-oleyl-1,3-diaminopropane). “Duomeens” are commercially available fromArmak Chemical Co., Chicago, Ill.

Such alkylenepolyamines include methylenepolyamines, ethylenepolyamines,butylenepolyamines, propylenepolyamines, pentylenepolyamines, etc. Thehigher homologs and related heterocyclic amines such as piperazines andN-amino alkyl-substituted piperazines are also included. Specificexamples of such polyamines are ethylenediamine, triethylenetetramine,tris-(2-aminoethyl)amine, propylenediamine, trimethylenediamine,tripropylenetetramine, tetraethylenepentamine, hexaethyleneheptamine,pentaethylenehexamine, etc. Higher homologs obtained by condensing twoor more of the above-noted alkyleneamines are similarly useful as aremixtures of two or more of the aforedescribed polyamines.

In one embodiment the polyamine is an ethylenepolyamine. Such polyaminesare described in detail under the heading Ethylene Amines in KirkOthmer's “Encyclopedia of Chemical Technology”, 2d Edition, Vol. 7,pages 22-37, Interscience Publishers, New York (1965).Ethylenepolyamines are often a complex mixture of polyalkylenepolyaminesincluding cyclic condensation products.

Other useful types of polyamine mixtures are those resulting fromstripping of the above-described polyamine mixtures to leave, asresidue, what is often termed “polyamine bottoms”. In general,alkylenepolyamine bottoms can be characterized as having less than 2%,usually less than 1% (by weight) material boiling below about 200 C. Atypical sample of such ethylene polyamine bottoms obtained from the DowChemical Company of Freeport, Tex. designated “E-100”. Thesealkylenepolyamine bottoms include cyclic condensation products such aspiperazine and higher analogs of diethylenetriamine,triethylenetetramine and the like. These alkylenepolyamine bottoms canbe reacted solely with the acylating agent or they can be used withother amines, polyamines, or mixtures thereof. Another useful polyamineis a condensation reaction between at least one hydroxy compound with atleast one polyamine reactant containing at least one primary orsecondary amino group. The hydroxy compounds are preferably polyhydricalcohols and amines. The polyhydric alcohols are described below. (Seecarboxylic ester dispersants.) In one embodiment, the hydroxy compoundsare polyhydric amines. Polyhydric amines include any of theabove-described monoamines reacted with an alkylene oxide (e.g.,ethylene oxide, propylene oxide, butylene oxide, etc.) having from twoto about 20 carbon atoms, or from two to about four. Examples ofpolyhydric amines include tri-(hydroxypropyl)amine,tris-(hydroxymethyl)amino methane, 2-amino-2-methyl-1,3-propanediol,N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine, andN,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine, preferablytris(hydroxymethyl)aminomethane (THAM).

Polyamines which react with the polyhydric alcohol or amine to form thecondensation products or condensed amines, are described above.Preferred polyamines include triethylenetetramine (TETA),tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), andmixtures of polyamines such as the above-described “amine bottoms”.

These extreme pressure additives can be used individually or in the formof mixtures, conveniently in an amount within the range from 0.1 to 2parts by weight, per 100 parts by weight of the base oil. All the abovecan be performance enhanced using a variety of cobase stocks, AN, AB,ADPO, ADPS, ADPM, and/or a variety of mono-basic, di-basic, and tribasicesters in conjunction with low sulfur, low aromatic, low iodine number,low bromine number, high analine point, isoparafin.

Examples

We have run several tests to show the benefits of the inventiveformulation. As shown in Table 2, seven examples were run and arelabeled Examples A, B, C, D, E, F, and G.

TABLE 2 Descriptions Type A B C D E F G Group I 150 SUS neutral BaseStock bal 98.27 Group II 4 cst at 100 C. Base Stock 10 19.5 19.5 19.2919.835 Group III 6 cst Base Stock 84.1 79 79 79 70 at 100 C. Group VBase Stock 3 borated Mannich base Dispersant 0.2 0.4 0.25 0.4 (boratedpolyisobutylene- phenol + formaldehyde & treata-ethylene pentamine)PIBSA-TEPA Dispersant 0.2 PIBSA (polyisobutylene Dispersant 1.0 succinicanhydride) polyol ester Demulsifier 0.01 0.01 0.01 0.01 poly oxyalkylenealcohol Demulsifier 0.01 0.01 0.02 0.02 oxyalkylated sorbitolDemulsifier metal sulfonate Demulsifier 0.3 Aromatic Amine Antioxidant0.5 0.6 0.6 0.6 0.4 0.3 Hindered Phenolic Antioxidant 0.5 0.3 0.3 0.30.3 0.3 metal passivator metal 0.01 0.1 0.03 passivator rust inhibitorrust 0.2 0.2 0.2 0.2 0.2 0.12 inhibitor non Si defoamant Defoamant 0.150.15 0.15 0.15 0.15 Si defoamant Defoamant 0.01 0.02 pour depressantpour 0.03 0.03 0.03 0.03 0.03 0.1 0.03 depressant phosphorus AntiwearAntiwear 0.6 Rotary Pressure Vessel 1258 1232 1168 2623 141 965 Oxid -Turbine Oil 504 HR 120 C. DRY TOST 100 mg/kg 63 405 23 4 56 5602 47sludge max [1] Emulsion Characteristics 41-39-0 41-39-0 41-39-0 41-38-140-39-1 40-39-1 0-0-80 @ 54° C. D-1401 Time Emulsion Characteristics 30Max to 10 10 20 30 25 15 >60 @ 54° C. 3 ml emul [1] ElectricalConductivity at 50 pS/m at 5 65 114 — 32° F. D4308 32 F. min [3]Electrical Conductivity at 12 97 167 70° F. D4308 D5185 CALCIUM, PPM [2]<0.5 <0.5 <0.5 <0.5 0.5 64 <2 D5185 PHOSPHORUS, <5 <5 <5 16 20 689 <5PPM D5185 ZINC, PPM 10 Max [1] <0.5 <0.5 0.6 <0.5 0.9 <0.5 <2

Blends C, D, and E are formulations showing various inventiveembodiments. Blends A, B, F, and G are typical commercial gas turbineengine oils for comparison. As can be shown in table 2, inventiveexamples C, D, and E have superior properties in the 504 Hour 120° C.Dry TOST sludge test compared to comparative Examples A, B, and F.Example A has neither the polyol ester demulsifier nor the Mannich baseddispersant. Example B has the polyol ester demulsifier but not themannich based dispersant. Example F has the mannich based dispersant butnot the polyol ester. Example G is a typical Group I commercial gasturbine oil which provides adequate deposit control but has thedrawbacks of Group I base stocks with poor emulsion characteristics.

TABLE 3 Chemical names Components Candidate 1 Candidate 2 1DiPhenylamine type Antioxidant 1 0.3 0.3 Hindered phenol Antioxidant 20.3 0.3 PANA type Antioxidant 3 0.3 0.3 Rust inhibitor Rust inhibitor 10.2 0.2 Dithiocarbamate Metal passivator 1 0.2 0.2 Tolytrizole typeMetal passivator 2 0.01 0.01 Ashless dithiophosate Antiwear 0.008 0.008Mannich based dispersant Dispersant 0.35 0.35 Polyol ester Demulsifier 10.02 0.02 Mixed polyether Demulsifier 2 0.01 EO-PO block copolymerDemulsifier 3 0.01 Non-Si defoamant Defoamant 0.2 0.2 Pour pointdepressant PPD 0.01 0.01 Alkylated Naphthalene Gp V 3 3 Group III Gp III16.282 16.282 Group III Gp III 79 79 Method/Description Description UnitMHI/120 C. Dry TOST (504 hours) Sludge mg/kg 6 5 MHI/RPVOT after 500 hrsOxidation Stability retention min % 1073/97% 1224/93% MHI/120 C. DryTOST (1000 hrs) Sludge mg/kg 18 40 D2272/RPVOT after 1000 hrs OxidationStability retention %  870/79% 1124/85% D1401/at 54 C./EmulsionCharacteristics ASTM Time min 20, 15 15, 15 D1401/at 54 C./EmulsionCharacteristics Oil-Water-Emulsion (ml) mL 39-39-2, 40-37-3 40-39-1,40-37-3 D2272/Rotary Pressure Vessel Oxid - RPVOT min 1101 1315 TurbineOil DIN 51354/FZG Fail Stage 10 10

Table 3 shows the benefit of adding a smaller amount of Pluronic L 121to the inventive formulation. Example I shows unexpected improvement inthe sludge test compared to Example H which is identical except for thePluronic L 121.

Examples C, D, and E all have favorable deposit control and emulsioncharacteristics. This demonstrates the importance in this embodiment, ofhaving either a Group II or Group III base stocks or combination thereofand having both a mannich based dispersant, a polyol ester and apolyakeleyne demulsifier.

While the examples are mostly to gas turbine engine oil formulations.Persons skilled in the art would recognize the applicability to allsituations where a good deposit control and emulsion properties aredesired. Other suitable uses include but are not limited to compressorand hydraulic oils. Applicants intend to capture all situations in whichthe claimed lubricant would be beneficial.

1. A lubricating oil with favorable deposit varnish properties,comprising a) a major amount of base stock selected from the groupconsisting of Group II, Group III, GTL and any combination thereof; b) amannich based dispersant comprising at least 0.1 and less than 2.0weight percent of the lubricating oil; c) a demulsifier comprising apolyol ester and a poly oxyakylene alcohol, the demulsifiers comprisingat least 0.002 to less than 2.0 weight percent of the lubricating oil;and d) the lubricating oil has a deposit control value less than 60using 504 hour 120° C. Dry TOST sludge test.
 2. The lubricating oil ofclaim 1 further comprising at least one additive selected from the groupconsisting of an antiwear additive, metal passivator, demulsifier, pourpoint depressant, rust inhibitor, defoamant and any combination thereof.3. The lubricating oil of claim 1 wherein the lubricating oil is a gasturbine oil.
 4. The lubricating oil of claim 1 wherein the polyol esterin the demulsifier comprises less than 25 wt % of the demulsifier andhas a molecular weight less than 5000 and the lubricating oil has a ASTMD-1401 emulsion characteristic of less than 60 at 54° C.
 5. Thelubricating oil of claim 1 wherein the lubricating oil has a ASTM D-4308electrical conductivity value of greater than
 50. 6. The lubricating oilof claim 1 wherein the lubricating oil has less than 5 PPM calcium andless than 5 PPM zinc.
 7. The lubricating oil of claim 6 wherein thelubricating oil has a less than 50 PPM phosphorous.
 8. A method ofimproving the deposit control comprising: a) obtaining a lubricating oilwith favorable deposit varnish properties, comprising a major amount ofbase stock selected from the group consisting of Group II, Group III,GTL and any combination thereof, a mannich based dispersant comprisingat least 0.1 and less than 2.0 weight percent of the lubricating oil, ademulsifier comprising a polyol ester and a poly oxyakylene, thedemulsifiers comprising at least 0.002 to less than 2.0 weight percentof the lubricating oil, wherein the lubricating oil has a depositcontrol value less than 60 using 504 hour 120° C. Dry TOST sludge test;and b) lubricating with the lubricating oil.
 9. The lubricating oil ofclaim 8 further comprising at least one additive selected form the groupconsisting of an antiwear additive, metal passivator, demulsifier, pourpoint depressant, rust inhibitor, defoamant and any combination thereof.10. The lubricating oil of claim 8 wherein the lubricating oil is a gasturbine oil.
 11. The lubricating oil of claim 8 wherein the polyol esterin the demulsifier comprises less than 25 wt % of the demulsifier andhas a molecular weight less than 5000 and the lubricating oil has a ASTMD-1401 emulsion characteristic of less than 60 at 54° C.
 12. Thelubricating oil of claim 8 wherein the lubricating oil has a ASTM D-4308electrical conductivity value of greater than
 50. 13. The lubricatingoil of claim 8 wherein the lubricating oil has a less than 5 PPM calciumand less than 5 PPM zinc.
 14. The lubricating oil of claim 13 whereinthe lubricating oil has a less than 50 PPM phosphorous.
 15. A method ofblending a oil to provide improved deposit control and favorableemulsion properties comprising: a) obtaining a major amount of basestock selected from the group consisting of Group II, Group III, GTL andany combination thereof, a mannich based dispersant comprising at least0.1 and less than 2.0 weight percent of the lubricating oil, ademulsifier comprising a polyol ester and a poly oxyakylene, thedemulsifiers comprising at least 0.002 to less than 2.0 weight percentof the lubricating oil; and b) formulating the base stocks, demulsifiersand dispersants to have a deposit control value less than 60 using 504hour 120° C. Dry TOST sludge test.
 16. The lubricating oil of claim 15further comprising at least one additive selected from the groupconsisting of an antiwear additive, metal passivator, demulsifier, pourpoint depressant, rust inhibitor, defoamant and any combination thereof.17. The method of claim 15 wherein the polyol ester in the demulsifiercomprises less than 25 wt % of the demulsifier and has a molecularweight less than 5000 and the lubricating oil has a ASTM D-1401 emulsioncharacteristic of less than 60 at 54° C.
 18. The lubricating oil ofclaim 1 further comprising a propylene oxide block copolymer.
 19. Thelubricating oil of claim 8 further comprising a propylene oxide blockcopolymer.
 20. The lubricating oil of claim 15 further comprising apropylene oxide block copolymer.